lib/Target/XCore/XCoreSelectionDAGInfo.cpp

   1 //===-- XCoreSelectionDAGInfo.cpp - XCore SelectionDAG Info ---------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the XCoreSelectionDAGInfo class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "XCoreTargetMachine.h"
  15 using namespace llvm;
  16
  17 #define DEBUG_TYPE "xcore-selectiondag-info"
  18
  19 SDValue XCoreSelectionDAGInfo::
  20 EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl, SDValue Chain,
  21                         SDValue Dst, SDValue Src, SDValue Size, unsigned Align,
  22                         bool isVolatile, bool AlwaysInline,
  23                         MachinePointerInfo DstPtrInfo,
  24                         MachinePointerInfo SrcPtrInfo) const
  25 {
  26   unsigned SizeBitWidth = Size.getValueType().getSizeInBits();
  27   // Call __memcpy_4 if the src, dst and size are all 4 byte aligned.
  28   if (!AlwaysInline && (Align & 3) == 0 &&
  29       DAG.MaskedValueIsZero(Size, APInt(SizeBitWidth, 3))) {
  30     const TargetLowering &TLI = *DAG.getSubtarget().getTargetLowering();
  31     TargetLowering::ArgListTy Args;
  32     TargetLowering::ArgListEntry Entry;
  33     Entry.Ty = DAG.getDataLayout().getIntPtrType(*DAG.getContext());
  34     Entry.Node = Dst; Args.push_back(Entry);
  35     Entry.Node = Src; Args.push_back(Entry);
  36     Entry.Node = Size; Args.push_back(Entry);
  37
  38     TargetLowering::CallLoweringInfo CLI(DAG);
  39     CLI.setDebugLoc(dl)
  40         .setChain(Chain)
  41         .setCallee(TLI.getLibcallCallingConv(RTLIB::MEMCPY),
  42                    Type::getVoidTy(*DAG.getContext()),
  43                    DAG.getExternalSymbol("__memcpy_4",
  44                                          TLI.getPointerTy(DAG.getDataLayout())),
  45                    std::move(Args), 0)
  46         .setDiscardResult();
  47
  48     std::pair<SDValue,SDValue> CallResult = TLI.LowerCallTo(CLI);
  49     return CallResult.second;
  50   }
  51
  52   // Otherwise have the target-independent code call memcpy.
  53   return SDValue();
  54 }